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D V ET L Oct. 15, 1929. J A A BY A Re. 17,457

AIR COMPRESSOR s ,Sheefs-Sheet 1 Original Filed March 16, 1925 ggwirau J. A. DAVEY ET AL AIR COMPRESSOR Oct. 15, 1929.

Original Filed March 16, 1925 Reissued Oct. 15,

, UNITED STATES PATENT OFFICE '1 JAMES A. DAVEY, OF SOUND BEACH,CONNECTICUT, AND PAUL H. DAVEY AND GHABLES L. GAUGLER, OF KENT, OHIO; SAID GAUGLER ASSIGNOB TO THE; DAVEY TREE Ex' PERT COMPANY, OF KENT, OHIO, A CORPORATION OF OHIO AIR comrnnsson Original No. 1,836,291, dated July 19, 1927', Serial No. 15,717, filed March 16, 1925. Reissue No. 16,872, 7 dated February 7, 1928, Serial No. 235,098, filed November 22, 1927. This application for reissue filed March 15, 1929. Serial N0. i l 7,427.

This invention relatesto air compressors, and particularly to an air compressor of the portable type adapted to be coupled with an automotive vehicle for driving the compressor. This application is a continuation in part of our application Serial No. 7 03,098, filed March 31, 1924, patent No. 1,685,150.

A portable air compressor of this type is of great value for supplying portable air 10 driven tools, as, for example, saws, chipping tools, riveters, or the like, and isv particularly useful where the tools must be taken to the work.

We provide an air compressor of simple and rugged construction which may be, attached to the frame of an automotive vehicle and operative connection made to the engine thereof for driving the compressor. As the vehicle is always stationary when the com- 3 pressor is in use, we provide auxiliary cooling means for the engine and also provide for cooling the compressor. We have found that it is highly desirable to prpvide this additional cooling means as the compres-- sor imposes a heavy load on the engine and the efficiency of thecooling means usually provided is reduced by reason of the fact that the vehicle is standing stationary.

In apparatus of this character it ishighly desirable to keep thBcCOIlStIllCtlOD as light as is consistent with good construction, and we have found that the ordinary valve mecha- 'nism will not stand up under the severe conditions imposed upon portableapparatus of this character. We therefore construct the cylinder heads and adjacent portions of the apparatus of a metal having very high thermal conductivity, as, for example, aluminum, and provide for discharging air outwardly 40 against the inner surface of this head. a We have found that the particular construction which We employ is highly desirable in'this form of compressor and gives exceptionally good results. 7

We preferably employ an air compressor having two opposed cylinders but have found that in' any event the intermittent load imposes an extremel heavy load upon the connection between t e compressor and the engine. We have found that where an unyieldof Figure 6;

ing connection is employed the parts will break and very unsatisfactory results are ob tained. We provide a flexible driving con- Figure 3 is a side elevation of aconnecting member used for attaching the compressor to the framework of the automotive vehicle; Flgure 4 1s a section on line IVfIV of VV of Figure 2; 5

Figure 6 is a view to an enlarged scale of the valve mechanism shown in the right hand portion of Figure 1;

Figure 7 is a section on the line VII -VII Figure 3;

Figure 5 1s a'section on the line FigureS is a view to an enlarged scale of the clutch mechanism shown in Figure 2; and

Figure 9. is an end View of the structure shown in Figure 8.

In the illustrated embodiment of the invention there is provided a crank case 2 having a air of coaxial cylinders 3 attached thereto. T e cylinders are provided with pistons 4 connected to a crank pin 5 by connecting rods 6. The crank pin 5 is carried between two flywheels 7 and 8, the flywheel? being secured to a shaft 9 adapted to make power connection with the engine of an automotive vehicle and a the flywheel 8 being connected to a shaft 10 01? driving the air compressor and cooling an. j

Each cylinder is provided ,with a closure comprising a head 11 and a valve plate 12 interposed between the head and the end of the cylinder 3 said head and said valve plate constituting aremovable end closure for the cylinder. Bolts 13 pass through the flange tion 15terminat1ng in an air inlet opening 16. The valve plate 12 lies across this opening and is secured to the head by bolts 17 Air inlet openings 18 are provided and the inlet valve is in the form of a flat ring 19.

The valve 19 is pressed against the openings 18 by springs 20. "Each of these springs is carried in an arm 21, the several arms being integral with a bolt 22 secured in the valve plate 12 by a nut 23. A washer 24 is provided for spacing the arms away from the valveseat and this washer is also eiiective for iding the plate valve 19.. On a suction 'stro e of the piston, air is drawn through the openings 18 past the valve 19 into the cylinder. On the compression stroke the com pressed air passes outwardly through ports 25 past a plate valve 26. This plate is held against the valve seat by springs 27, the springs being carried by a ring, 28 which is threaded onto thevalveplate 12 as shown. The compressed air escapes into the head around the outside of the ring 28 and also through ports 29 provided therein.

While it is necessary to make the plate valves 19 and 26 and also the springs used in connection therewith of steel, it is preferred to make the remainder of the head from a metal having a high heat conductivity, 'such as aluminum. A difficulty Which has always been experienced heretofore in portable air compressors has been the proper cooling of the valve structure, and the form shown in the drawings has given exceptionally good results. vNot only is the head made of alumi-' num, which is of high heat conductivity, but this head is also provided with cooling fins 30. When the air is discharged around the outside of the ring 28, it strikes the aluminum wall of the head and a large portionof the heat of the compressed air is thereby removed; Similarly, any air passing through the ports 29 strikes against the walls of the conical portion 15 and is thus cooled. In addition to this the passage of cool air through the openings 18 to the inlet valve aids materlally in maintaining the valve mechanism at proper temperature.

Each of the heads is provided ith an outlet 31 for compressed air and these outlets are cennected by a cross pi e 32 which also is preferably providedwit cooling fins. The cross pipe 32 in the preferred form of-our invention is made of aluminum, as it is found that this aids in maintaining the desired low. temperature. ,v l The various parts of the compressor-are readily accessible, as will be apparent from Figure 1. If the screws 13 holding the heads on the cylinders and the screws 33 holding the cross pipe to the heads'are removed, a

head may be removed, together with its valve,

yon

ends engage the attachment plate 36. Thepreferably p such as bra e lining 53. The band 52 is socured to a connecting member 54 which is for inspection or.repair. The several parts of the valve may be quickly replaced so that even in the event of a break-down very little time will be consumed-in putting the apparatus back into working condition. A

breather pipe 34 isprovided for the crank case and an oil sight 35 is also provided. The air compressor is secured to the vehicle frame by a. connection plate 36 rigidly secured to the crank case 2. A pair of attachment members 37 are provided and are permanently secured in the channels 38 comprising a frame of the vehicle. They are provided with flan ed and threaded ends 39 projecting be- 5 the radiator 40 of the vehicle and these plate is secured tothese members by nuts 40.

We have found that in an apparatus like an air compressor where the load on the power shaft is extremel irregular, there is always a tendency for t 1e power connection to crystallize and break unless some flexibility is provided therein. We accordingly make a flexible connection between the shaft. 9 and the engine shaft '41 of the vehicle. A connection sleeve 42 is provided and to this is fastened a shaft 43 projecting through the opening usually provided adjacent the radiator for the engine crank. In the well known Ford automobile a pin is enerall provided through the head end of t e cran shaft for engagement by the crank. In making a connection to this type of engine, we remove this shaft we also provide draw bolts 45. These are so la ed in the sleeve 44 that aside portion 0 each b'olt projects into the space re quired for the shaft 41. The central opening of the sleeve is then bored out, leaving-a notch in each of the bolts 45, and after the sleeve is placed on the shaft the bolts are drawn up tight by nuts 46. It is found that this exerts a spring clamping action on the shaft and prevents any play at this point.

The shaft 43 is provided with a spider 47 to which are bolted one or more flexible connecting disks .48. These disks are preferably made of fabric impregnated with rubber, such as are used in the well knownThermoid-Hardy universal joint. The disks 48 are secured to the spider by spaced apart bolts 49 and intermediate them bolts 50 are provided for securing to the ring a drum 51. Surrounding the drum'51 is a band 52 which is rovided with a suitable lining,

carried .on a pin 55. secured to a plate' 56.

Diametrically opposite the pin 55 is a similar in-57 through which a bolt 58 passes and this bolt engages connection members 59 secured to the band 52. The plate 56 is secured to the shaft 9, and it will be seen that when the bolt 58is tightened there will be provided a driving connection between the engine shaft 41 and the air compressor. When the away from the drum, so'as t9. prevent heating. This clutch connection is particularly described and claimed in our copending application Serial No. 15,716, filed of even date herewith, patent No. 1,636,290.

The load imposed on the automobile en-- gine'of a large compressor is such'that the ordinary cooling system is not suflicient to maintain the engine at suitable running temperature. We therefore provide an auxiliary cooling fan 62 which is mountedin front of the radiator 40. This fan is carried on a shaft 63 having a belt pulley 64 adapted to be driven through a belt 65 from a pulley 66 mounted on the shaft 10. The shaft 63 is carried in a bearing member 67 which is eccentrically mounted in a bracket 68 and secured therein by bolts 69. This provides a convenient means for tightening or loosening the belt 65, as maybe required.

We provide an a1r compressor, of simple construction which may be readily attached to an automotive vehicle. The head and valve structure insures thorough cooling and is found in practice to give exceedingly good results. The cooling fan provided maintains the engine at the desired temperature and materially improves the operation of the entire apparatus. The valves are very simple and accessible and their construction and arrangement is practically desirable in a compressor of this type.

One reason is that the hot outlet annulus is outside the inlet annulus, so that its conductive path to the outer air is short; also the annular outlet valve 26 is of very great area as compared with the combined areas of the outlet passages 25. the proportions widthwise of the annulus being approximately three to one and circumferentially approximately six to one. This gives a relatively enormous area for quick heat transfer from thesteel plate valve 26 to the aluminum valve plate 12, particularly during the relatively long portion of each cycle, when this outlet valve is closedand in close heat transfer re- .lation to said aluminum valve plate 12;. also ment of our invention, it is understood that it is not limited thereto but may be otherwise embodied within the scopeof the following of the compressor.

2. An air compressorlncluding 'a cylinder, an end closure therefor, valves 1n said closure,

and means providing a metallic path of high heat conducting qualityand adequate capacity including an aluminum valve plate ex tending outward to the exterior of the com-" pressor.

- 3. An air compressor in cluding a cylinder, and a detachable aluminum"closure therefor said closure having valve seats therein and providing a path of high heat conducting quality and capacity to atmosphere.

4. An air compressor including a cylinder having a head and a valve plate interposed between-the cylinder and the head, both the "head and the valve plate being made of a metal of relatively high heat conductivity.

5. In combination with an automotive vehicle having a radiator, an air-cooled air compressor of large capacity requiring the motor to be run under heavy load conditions said compressor being mounted. adjacent the radiator, a driving connection between the engine of the vehicle and the compressor and a fan mounted on the compressor in front of the radiator.

6. In a combination with an automotive vehicle having an internal combustion engine and a main ,driving shaft thereof, an air compressor of large capacity requiring the engine therefor to be 'run under heavy load conditions said compressor mounted on said .vehicle and having a driving shaft arranged in alinement with said engine shaft, and a flexible coupling connecting said shafts comprising a flexible disk attached to one of the said shafts, a drum around the periphery of the disk, a flexible band connected to the other shaft and adapted to cooperate with the drum, and means for positively clamping the band around the drum to form a normally non-slipping driving connection, substantially as described.

7. In a combination with an automotive vehicle having an internal combustion engine and a main driving shaft thereof, an air compressor of large capacity requiring the engine therefor to be run under heavy load conditions said compressor mounted on said vehicle and having a driving shaft arranged in alinement with said engine shaft, and a flexible coupling connecting said shafts comprising a drum secured to one of said shafts and serving as one member of a clutch, a releasable clamping band encircling the drum and serving as the other member of the clutch, means to force the clamping band positively into clamping relation with said drum, supporting means for the band fixed to the other shaft, anda flexible disk' interposed between one of the clutch members and itsshaft. V

8. An air compressor including a cylinder, a closure therefor, thin, large-area valves in said closure, and means roviding a metallic path of 'high heat con uctin'g'quality and adequate capacit including an aluminum valve plate extenkhng outward to the exterior of the compressor. 9. An air compressor including a cylinder, and a detachable aluminum closure therefor having valve seats and plate valves therein, said closure providing a pathiof high heatconducting quality and capacity toatmosphere. v

10. An air-cooled ,air compressor of large capacity, including a cylinder, an aluminum end closure therefor 21 ording a path to the atmosphere of high heat conducting quality and capacity and having outlet passages therein, in combination with a single outlet valve covering and extending between aplurality of said passages, with one of its surfaces extending adjacent and inefl'ective heat transfer relation to the aluminum surfaces of said end closure around and between said outlet passages.

11. An air-cooled air compressor of large capacity, includin a cylinder, an aluminum end closure there or afl'ording a path to the atmosphere of high heat conducting quality and capacity, and having inlet and outlet pas sages therein, the outlet passages being an nularly arranged and of small aggregate area as compared with the area of theannulus, in combination with inlet and outlet valve for said passages, the outlet valve being a relatively thin annular surfaces extending a jacent and in effective heat transfer relation to the aluminum surfaces of said end closure around and between said outlet passages.

inlet and outlet passages and each 12. An air-cooled air compressor of large capacity, including a cylinder, an aluminum end closure therefor, affording a path to the atmosphere of high heat conducting quality and capacity havin annularly arranged inlet passages and annu arly arranged outlet passages surrounding said inlet passages, in combination with relatively thin annular. plate valves adapted to close their res tive slate having one of its the valve plate being made of a metal of relatively high heat conductivity and the head having cooling fins thereon.

15. An. air compressor including a cylinder, a closure therefor, a thin, large-area plate valvefor passages in said closurefand means providing a metallic path of high heat conducting quality and capacity from said valve to the exterior of the compressor.

16.' An air compressor including a compressipnchamber, a removable closuretherefor,-a valve for an outlet passage in said closure, and means providing a metallic path of high heat conducting quality and capacity from said valve to the exterior of the compressor. I

17. In an air cooled compressor, a cylinder, a closure therefor including a valve plate of met-a1 of high heat conducting capacity with an outer annular series of discharge openings and an inner annular series of inlet openings, a thin annular plate valve seating at one side of the valve plate and closing the outlet openings, and a thin annular plate valve seating at the other side of the valve plate and closing the inlet openings, whereby the inflowing air aids in maintaining the Valve mechanism at pro or temperature.

7 In testimony Whereo we afiix our signatures. I

JAMES A. DAVEY.

PAUL H. DAVEY. CHARLES L. GAUGLER.

aving large surface area adjacent and in effective heat transfer relation to the aluminum surfaces of the said end closure, around and be tween the several passages which said'valve closes,

13. An aircompressor including a com-; pression chamber, a removableclosure therefor, thin, large-area inlet and outlet plate valves for passages in said closure, and means 

